Sunbeam Twin Blade Electric Mower
Our next door neighbor had one these years ago that I fixed several times, this is indeed a fairly early one [ one these early ones they used two coged belts and you had to assemble them properly so the two blades would not strike each other at the blade tips, like a beaters on a food mixer ] I have a later SB TB mower and on these they moved one blade ahead of the other to eliminate the interference problem.
This little mower would be plenty big enough for your yard. Electric mowers today are so good I cannot imagine why anyone would still buy Middle Eastern oil to cut their lawns. The new rechargeable electrics are the perfect way to mow up to around an acre of lawn, these mowers are safer, more reliable, quieter and just an all around more civilized way to cut grass.